Changing relationship between bones

ABSTRACT

To change a spatial relationship between two or more bones in a patient&#39;s body, a wedge member is moved into a joint between the bones. As the wedge member enters the joint, pivotal movement occurs between the bones to change the orientation of the bones relative to each other. The wedge member may have a circular cross sectional configuration and be moved into the joint by rotating the wedge member about an axis which extends between a thin leading edge portion and a thick trailing edge portion of the wedge member. Alternatively, the wedge member may have a cam-shaped configuration and be rotated through less than a revolution to apply force against the bones. The wedge member may have a porous construction which enables bone to grow through the wedge member and immobilize the joint. The wedge member may be coated with and/or contain bone growth promoting material. The wedge member may be connected to only one of the bones or may be connected to two adjacent bones. If the wedge member is connected to only one bone, the joint may be capable of being flexed after the wedge member is inserted into the joint.

BACKGROUND OF THE INVENTION

[0001] The present invention relates to a new and improved method ofchanging a spatial relationship between bones which are interconnectedat a joint in a patient's body.

[0002] It has previously been suggested that joints between bones befused, that is, surgically immobilized, to promote patient comfort.Thus, U.S. Pat. No. 5,026,373 suggests that a fusion cage be positionedbetween adjacent vertebrae. Perforations are formed in the cage. Thecage is packed with a bone-inducing substance. A method for immobilizingvertebrae is also disclosed in U.S. Pat. No. 5,015,255.

[0003] It has previously been suggested that the spatial relationshipbetween portions of a bone in a patient's body be changed to correctdeformities. This may be done by removing a wedge-shaped piece of bonein the manner disclosed in U.S. Pat. No. 5,601,565.

[0004] Another method of changing the spatial relationship betweenportions of a bone in a patient's body includes forming a slot in thebone. A forked wedge tool is inserted into the slot. A plate is thenplaced in a central opening in the forked wedge tool and positionedagainst the bone. The plate is secured to the bone. The forked wedgetool is then removed from the opening. This method of changing thespatial relationship between portions of a bone in a patient's body isdisclosed in U.S. Pat. No. 5,620,448.

[0005] A method and apparatus for use in changing a spatial relationshipbetween portions of a bone in a patient's body is also disclosed inco-pending U.S. patent application Ser. No. 09/109,126, filed Jun. 30,1998 by Peter M. Bonutti and entitled Method And Apparatus For Use InOperating On A Bone. This application discloses the use of a wedgemember to expand a slot formed in a bone. The wedge member is porous andmay be coated with and/or contain bone growth promoting material. Thewedge member may have a configuration which corresponds to aconfiguration of a portion of the bone which is engaged by the wedgemember. Alternatively, the wedge member disclosed in the aforementionedapplication Ser. No. 09/109,126 may have a circular cross sectionalconfiguration with an external thread convolution to enable the wedgemember to be moved into an opening in a bone by rotating the wedgemember.

SUMMARY OF THE INVENTION

[0006] A new and improved method and apparatus is provided to change aspatial relationship between bones which are interconnected at a jointin a patient's body. When this is to be done, an opening is formed in aportion of the patient's body to expose the joint interconnecting thebones. One of the bones is moved relative to the other by expanding atleast a portion of the joint with a wedge member. The wedge member ismoved into the joint and applies force against the bones. The opening isclosed with the wedge member still disposed in the joint between thebones. Force is then transmitted between the bones through the wedgemember to maintain the joint in an expanded condition.

[0007] If the joint is to be flexed after being expanded by the wedgemember, the wedge member may be connected with only one of the bones.Alternatively, if the joint is to be immobilized (fused) after insertingthe wedge member, the wedge member may be fixedly connected with thebones interconnected at the joint. The wedge member may be porous andmay be coated with and/or contain bone growth promoting material.

[0008] One embodiment of the wedge member has major side surfacesextending between thick and thin end portions of the wedge member. Thewedge member is moved into the joint with the thin end portion leading.As the wedge member is moved into the joint, the thick trailing endportion of the wedge member expands the joint.

[0009] In another embodiment of the invention, the wedge member isrotated relative to the joint to expand the joint. The wedge member mayhave a circular cross sectional configuration and an external threadconvolution which extends from a thin leading end of the wedge member toa thick trailing end of the wedge member. The wedge member is pressedinto the joint and rotated to cause the wedge member to expand thejoint.

[0010] In another embodiment of the invention, the wedge member hassurface areas which are relatively close together and other surfaceareas which are relatively far apart. The wedge member is moved into thejoint with the surface areas which are close together engaging theadjacent bones. The wedge member is then rotated to apply force againstthe adjacent bones to expand the joint. The wedge member may be rotatedabout its central axis to apply forced against the bones and expand thejoint. Alternatively, the wedge member may be rotated about a locationwhere the wedge member engages one of the bones.

[0011] Regardless of which embodiment of the wedge member is selected,the wedge member may be used with any one of the many different bonesand joints in a patient's body. The wedge member may be utilized atjoints in a patient's wrist, ankle, hand, foot, back or other portionsof the patient's body. The wedge member may be particularly advantageouswhen a joint between vertebrae in patient's back is to be immobilized.One or more wedge members may be used to expand a joint and transmitforce between bones.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The foregoing and other features of the present invention willbecome more apparent from the following description taken in connectionwith the accompanying drawings wherein:

[0013]FIG. 1 is a schematic illustration depicting the spatialrelationship between bones at a joint in a patient's body;

[0014]FIG. 2 is a schematic illustration depicting the manner in which awedge member is inserted into the joint between the bones of FIG. 1 toexpand a portion of the joint and change the spatial relationshipbetween the bones;

[0015]FIG. 3 is a schematic illustration of another embodiment of theinvention in which the joint of FIG. 1 is flexed after the wedge memberhas been inserted into the joint and connected with only one of thebones;

[0016]FIG. 4 is a schematic illustration depicting an alternative mannerof inserting the wedge member into the joint between the bones of FIG.1;

[0017]FIG. 5 is a schematic pictorial illustration of the wedge memberof FIGS. 2 and 3;

[0018]FIG. 6 is a plan view further illustrating the construction of thewedge member of FIG. 5;

[0019]FIG. 7 is a side view, taken generally along the line 7-7 of FIG.6, of the wedge member of FIG. 5;

[0020]FIG. 8 is an enlarged fragmentary schematic sectional viewdepicting the manner in which the wedge member of FIGS. 5-7 ispositioned, as shown in FIG. 2, in a joint between bones;

[0021]FIG. 9 is a fragmentary schematic sectional view, generallysimilar to FIG. 8, but on a reduced scale, illustrating an embodiment ofthe invention in which the wedge member is porous;

[0022]FIG. 10 is a fragmentary schematic sectional view, generallysimilar to FIG. 9, illustrating an embodiment of the wedge member whichis porous and has a chamber which holds bone growth promoting material;

[0023]FIG. 11 is a fragmentary schematic sectional view, generallysimilar to FIGS. 8-10, illustrating the manner in which the wedge memberof FIG. 3 is connected with only one bone to enable the joint betweenbones to be flexed;

[0024]FIG. 12 is a schematic illustration depicting the manner in whicha rotatable wedge member is moved into a joint between bones;

[0025]FIG. 13 is a schematic illustration depicting the wedge member ofFIG. 12 after the wedge member has been rotated to expand a portion ofthe joint between the bones;

[0026]FIG. 14 is an enlarged fragmentary schematic sectional view, takengenerally along the line 14-14 of FIG. 12, illustrating the relationshipof the rotatable wedge member to the bones prior to rotation of thewedge member;

[0027]FIG. 15 is an enlarged fragmentary schematic sectional view, takengenerally along the line 15-15 of FIG. 13, illustrating the relationshipof the rotatable wedge member of FIG. 14 to the bones after rotation ofthe wedge member;

[0028]FIG. 16 is a fragmentary schematic sectional view, taken generallyalong the line 16-16 of FIG. 15, illustrating the manner in which therotatable wedge member is connected with the bones;

[0029]FIG. 17 is a fragmentary schematic sectional view, generallysimilar to FIG. 16, illustrating an embodiment of the rotatable wedgemember which is porous;

[0030]FIG. 18 is a fragmentary sectional view, generally similar to FIG.14, illustrating the relationship between the bones at a joint whenanother embodiment of the rotatable wedge member is in the initialorientation illustrated in FIG. 12 relative to the bones;

[0031]FIG. 19 is a fragmentary schematic sectional view, generallysimilar to FIG. 15, illustrating the relationship of the rotatable wedgemember of FIG. 18 to the bones after the wedge member has been rotated;

[0032]FIG. 20 is a fragmentary schematic sectional view, taken generallyalong the line 20-20 of FIG. 19, further illustrating the constructionof the rotatable wedge member;

[0033]FIG. 21 is a schematic illustration, generally similar to FIG. 2,depicting the manner in which another embodiment of the rotatable wedgemember is moved into a joint between bones in a patient's body;

[0034]FIG. 22 is an enlarged schematic pictorial illustration of therotatable wedge member of FIG. 21;

[0035]FIG. 23 is a fragmentary schematic illustration, generally similarto FIG. 2, depicting the manner in which another embodiment of the wedgemember is moved into a joint between bones in a patient's body; and

[0036]FIG. 24 is an enlarged fragmentary schematic sectional view, takengenerally along the line 24-24 of FIG. 23, further illustrating therelationship of the wedge member to the bones.

DESCRIPTION OF SPECIFIC PREFERRED EMBODIMENTS OF THE INVENTION

[0037] General Description

[0038] An upper or first bone 30 in a patient's body is illustratedschematically in FIG. 1. A lower or second bone 32 is connected with theupper bone 30 at a joint 34. The bones 30 and 32 and joint 34 have beenillustrated schematically to represent any one of many bones and jointsin a patient's body. Thus, the bones 30 and 32 and joint 34 may bedisposed in a patient's hand, foot, back, or other portion of thepatient's body. It should be understood that the bones 30 and 32 andjoint 34 have been illustrated schematically in FIG. 1 as beingrepresentative of any one of the many joints in a human patient's bodyand it is not intended to limit the present invention to any particularjoint.

[0039] In order to correct deformities, improve patient comfort or otherreasons, it may be desired to change the spatial relationship betweenthe upper and lower bones 30 and 32. Thus, it may be desired to changethe angular relationship between longitudinal central axes 38 and 40from the relationship illustrated schematically in FIG. 1 to therelationship illustrated schematically in FIG. 2.

[0040] In order to change the spatial relationship between thelongitudinal central axes 38 and 40 of the bones 30 and 32, an openingis formed in a portion of the patient's body to expose the joint 34. Awedge member 44 (FIG. 2) is moved into the exposed joint 34 between thebones 30 and 32. The wedge member 44 applies force against the outerside surfaces of the bones 30 and 32 at the joint 34 to expand a portionof the joint.

[0041] As the wedge member 44 is moved into the joint 34, in the mannerillustrated schematically in FIG. 2, the lower bone 32 is pivotedrelative to the upper bone 30 about an axis extending through the joint34. This changes the angular orientation of the lower bone 32 relativeto the upper bone 30. Thus, the spatial relationship between the upperand lower bones 30 and 32 is changed from the spatial relationshipillustrated in FIG. 1 to the spatial relationship illustrated in FIG. 2by the wedge member 44.

[0042] In FIG. 2, the wedge member 44 has been illustrated schematicallyas having an extent which corresponds to approximately one-half of theextent of the joint 34. However, it is contemplated that the wedgemember 44 could have an extent which is either smaller than or greaterthan the extent illustrated in FIG. 2. Thus, the distance between thethick and thin end portions of the tapered wedge member 44 may be lessthan one-half of the width of the joint 34. Similarly, the distancebetween the thin leading end portion and thick trailing end portion ofthe wedge member 44 may be greater than one-half of the width of thejoint 34.

[0043] The wedge member 44 may be relatively narrow, as measured alongthe thin end portion of the wedge member. This would enable a pluralityof narrow wedge members 44 to be used to expand a single joint 34. Ifthe wedge member 44 is relatively wide, only a single wedge member maybe required to expand a joint 34, as shown in FIG. 2.

[0044] In the embodiment of the invention illustrated in FIG. 2, thejoint 34 is fused after the joint has been expanded by the wedge member44 to change the spatial relationship between the bones 30 and 32. Thus,after the joint 34 has been expanded by the wedge member 34, the jointis immobilized with the upper and lower bones 30 and 32 in the spatialrelationship illustrated in FIG. 2. When the wedge member 44 is utilizedin association with joints between vertebrae in a patient's back, it isbelieved that it may be particularly advantageous to immobilize thejoint 34.

[0045] Immobilization of the joint 34 may be accomplished by connectingthe wedge member 44 with both the upper bone 30 and the lower bone 32.Immobilization of the joint 34 may also be accomplished by the growth ofbone and/or other body tissue between the two bones 30 and 32 at thejoint 34. Known bone growth promoting materials may be provided at thejoint 34 if desired. The bone growth promoting materials may includebone morphogenic proteins and/or other osteoinductive materials.

[0046] In the embodiment of the invention illustrated in FIG. 3, thejoint 34 is capable of being flexed after the wedge member 44 has beenutilized to expand a portion of the joint. Thus, once the wedge member44 has been inserted into the joint 34, in the manner illustrated inFIG. 2, the patient may flex the joint under the influence of forcetransmitted to the bones 32 and 30 from muscle tissue in the patient'sbody.

[0047] When the joint 34 is flexed, as illustrated schematically in FIG.3, the bone 32 moves away from the wedge member 44. The wedge member 44is fixedly connected to only the bone 30. This allows the bone 32 tomove away from the wedge member. It is believed that it will beparticularly advantageous to enable the joint 34 to be flexed when thewedge member is utilized to correct deformities occurring in hands,feet, wrists or ankles of a patient. However, it should be understoodthat the wedge member could be attached to a single bone at any joint ina patient's body which is to be flexed after the wedge member has beenused to expand the joint.

[0048] In the embodiment of the invention illustrated in FIGS. 1-3, thewedge member 44 has been shown as being moved into the joint 34 in adirection which is perpendicular to an axis about which the joint isflexed. Thus, the wedge member 44 is moved into the joint 34 (FIG. 2) ina direction perpendicular to the axis about which the joint 34 isschematically illustrated in FIG. 3 as being flexed.

[0049] In the embodiment of the invention illustrated in FIG. 4, thewedge member 44 is inserted into the joint 34 in a direction parallel tothe axis about which the joint is normally flexed. Thus, the wedgemember 44 is illustrated in FIG. 4 as being inserted into the joint 34in a direction perpendicular to the plane of the drawing of the joint 34in FIGS. 1 and 3. It should be understood that the wedge member 44 couldbe inserted into a joint, such as the joint 34, in any desired directionin order to obtain a desired expansion of the joint. Thus, the wedgemember 44 could be moved into the joint 34 along a path which is neitherperpendicular to or parallel to the axis about which the joint isflexed.

[0050] After one or more wedge members 44 have been positioned in ajoint 34, in the manner previously explained, the opening in thepatient's body is closed. When the opening in the patient's body isclosed, the wedge member 44 remains in the joint 34 between the bones 30and 32. The wedge member 44 is formed of a rigid material which iscapable of transmitting force between the bones 30 and 32 immediatelyafter being positioned in the joint 34. Therefore, the wedge member 44is effective to maintain the changed spatial relationship, such as thespatial relationship illustrated in FIG. 2, between the bones 30 and 32during loading of the joint 34 immediately after positioning of thewedge member in the joint.

[0051] Wedge Member

[0052] The wedge member 44 (FIGS. 5-7) tapers from a thick end portion50 to a thin end portion 52. The wedge member 44 has flat upper andlower major side surfaces 54 and 56 (FIG. 7) which slope toward eachother from the thick end portion 50 to the thin end portion 52. Themajor side surfaces 54 and 56 intersect at the thin end portion 52. Thepointed thin end portion 52 of the wedge member 44 facilitates movingthe wedge member into the joint 34 between the bones 30 and 32 (FIG. 2).

[0053] In the illustrated embodiment of the wedge member 44 (FIGS. 5-7),the thick end portion 50 has an outer side surface 60 which forms aportion of a cylinder. The thin end portion 52 extends diametricallyacross the cylinder (FIG. 6). Therefore, the wedge member 44 has asemi-circular configuration. However, it should be understood that theconfiguration of the upper and lower major side surfaces 54 and 56 ofthe wedge member 44 corresponds to the configuration of the joint withwhich the wedge member is to be associated.

[0054] The semi-circular outer side surface 60 will, for many joints atleast, have an irregular configuration other than the semi-circularconfiguration illustrated in FIGS. 5 and 6. This enables the outer sidesurface 60 to be aligned with the outer side surfaces of the bones 30and 32 at the joint 34. Since most bones do not have outer side surfaceswhich form portions of a semi-circular, it is believed that in allprobability, the wedge member 44 will have an outer side surface 60 withan irregular configuration rather than the semi-circular configurationillustrated in FIG. 5.

[0055] The extent of the thin end portion 52 of the wedge member 44 maybe substantially less than shown in FIG. 6. Thus, the extent of the thinend portion 52 of the wedge member 44 may be less than one-half of theextent shown in FIG. 6. This would result in the major side surfaces 54and 56 of the wedge member 44 having a generally U-shaped configuration.Parallel triangular side surfaces would extend between the outer sidesurface 50 of the wedge member 44 and opposite ends of the thin endportion 52. These triangular side surfaces would be spaced from oppositesides of the joint 34 when the wedge member 44 is inserted into thejoint.

[0056] When the wedge member 44 has a relatively narrow, generallyU-shaped configuration, a plurality of the wedge members may be insertedinto a single joint 34 (FIG. 1). When a plurality of narrow wedgemembers 44 are used at one joint 34, the wedge members may havedifferent configurations. Thus, the wedge members 44 may have differentlengths and/or different angles between the upper and lower major sidesurfaces 54 and 56 of the wedge members.

[0057] The upper and lower major side surfaces 54 and 56 of the wedgemember 44 slope toward each other from the thick end portion 50 to thethin end portion 52 of the wedge member. It is contemplated that aplurality of wedge members 44 having different acute angles between theupper and lower major side surfaces 54 and 56 may be provided. Thiswould enable a surgeon to select the wedge member 44 having a desiredthickness at the thick end portion 50. Thus, if a surgeon determinesthat a joint should be expanded to either a lesser or greater amountthan would be accomplished by a wedge member having one angle, thesurgeon may select a wedge member having a different angle and thicknessto effect the desired expansion of the joint 34. It is also contemplatedthat a plurality of wedge members 44 having different widths, asmeasured along the thin end portion 52, may be provided.

[0058] The acute angle between the flat upper and lower major sidesurfaces 54 and 56 is determined by the extent to which the joint 34 isto be expanded, that is, the extent to which the spatial relationshipbetween the bones 30 and 32 is to be changed by insertion of the wedgemember 44. Of course, the specific angle provided between the upper andlower major side surfaces 54 and 56 of the wedge member 44 will varydepending upon the size of the joint with which the wedge member is usedand the extent to which the spatial relationship between the bones 30and 32 is to be changed by use of the wedge member. In addition, thelength and width of the wedge member 44 inserted into a particular jointwill be determined by the extent to which the joint is to be expandedand the total number of wedge members to be inserted into the joint.

[0059] It is believed that it may be desired to have the acute anglebetween the upper and lower major side surfaces 54 and 56 (FIG. 6) ofthe wedge member 44 within a range between one and thirty degrees.Although it is difficult to be certain, it is believed that it may bepreferred to have the acute angle between the upper and lower major sidesurfaces 54 and 56 of the wedge member 44 vary within a range of fivedegrees to twenty degrees. It should be understood that the foregoingspecific ranges of sizes for the angle between the upper and lower majorside surfaces 54 and 56 of the wedge member 44 have been set forthherein for purposes of clarity of description and it is contemplatedthat the angle between the upper and lower major side surfaces 54 and 56may be any one of many angles other than these specific angles.

[0060] The size of the wedge member relative to a specific joint 34 mayvary depending upon the deformity to be corrected. Thus, a narrow wedgemember 44 may have a thin end portion 52 (FIG. 6) with a length which isrelatively small compared to the width of a joint. The thin end portion52 of the narrow wedge member 44 could have a length of less than onefourth the distance across the joint. This would result in opposite endsof the thin end portion 52 being spaced from the periphery of the joint.It is contemplated that a plurality of narrow wedge members 44 could beused to expand a single joint.

[0061] The wedge member 44 may be formed of any one of many differentknown materials which are compatible with a patient's body. For example,the wedge member may be formed of human or animal bone, stainless steel,tantalum, a porous ceramic, or a polymeric material. If desired, thewedge member may be formed of a biodegradable material. However, it ispreferred to have the wedge member 44 formed of a rigid material whichis capable of enabling force to be transmitted through the joint 34between the bones 30 and 32 immediately after installation of the wedgemember in the joint.

[0062] In the embodiment of the invention illustrated in FIG. 2, thejoint 34 is immobilized. To facilitate immobilization of the joint 34,the wedge member 44 is fixedly connected with the bone 30 and with thebone 32. To facilitate fixedly connecting the wedge member 44 with thebones 30 and 32, a pair of passages 64 and 66 are formed in the wedgemember 44 (FIGS. 6 and 7). When the wedge member 44 is positioned in thejoint 34 (FIG. 2), suitable fasteners, that is screws 70 and 72 extendthrough the passages 64 and 66 into the bones 30 and 32 in the mannerindicated schematically in FIG. 8. The screws 70 and 72 engage hardcortical outer layers 76 and 78 of the bones 30 and 32. If desired, thescrews 70 and 72 could extend into the relatively soft cancellous bone80 and 82.

[0063] Although the wedge member 44 has been illustrated in FIG. 8 asbeing connected with the bones 30 and 32 by a pair of screws 70 and 72,it should be understood that the wedge member 44 may be connected withonly one of the bones 30 or 32 by only one of the screws 70 or 72 ifdesired. For example, if the wedge member 44 is connected with the bone30 by the screw 70, the joint 34 could be flexed in the mannerillustrated schematically in FIG. 3, after the wedge member 44 has beenmoved into the joint.

[0064] Positioning of Wedge Member

[0065] When the wedge member 44 is to be inserted in to the joint 34 tochange the spatial relationship between the bones 30 and 32 in themanner illustrated schematically in FIG. 2, a location for insertion ofthe wedge member into the joint 34 is selected by a surgeon. Thespecific location at which the wedge member 44 is inserted into thejoint 34 to expand the joint will be selected by the surgeon as afunction of the desired result from a particular operation. In addition,the size of the wedge member 44 will be selected by the surgeon as afunction of the joint and the result to be obtained from a particularoperation.

[0066] The configuration of the wedge member 44 will be selected by thesurgeon as a function of the location where the wedge member is to beinserted into the joint 34. The wedge member 44 may be relatively wideand have a long thin end portion 52, as shown in FIG. 6, to enable thethin end portion to extend between opposite sides of the joint.Alternatively, the wedge member 44 may be relatively narrow and have athin end portion 52 which is short. If this is done, the thin endportion 52 would not extend between opposite sides of the joint 34. Aplurality of the narrow wedge members 44 may be inserted into a singlejoint 34 to expand the joint and transmit force between the bones 30 and32.

[0067] The surgeon makes an incision in soft body tissue surrounding thejoint 34 to expose the joint. Once the joint 34 has been exposed, thethin end portion 52 (FIGS. 5 and 6) of the wedge member 44 is moved intothe joint 34. When the wedge member 44 is to be inserted into a joint inthe manner illustrated schematically in FIG. 2, the longitudinal centralaxis of the thin end portion 52 of the wedge member is aligned with anaxis about which the joint pivots. The wedge member is then moved intothe joint 34 along a linear path which extends perpendicular to the axisabout which the joint pivots. The wedge member 44 is moved into thejoint 34 by applying force against the trailing thick end portion 50 ofthe wedge member.

[0068] As the wedge member 44 is moved into the joint 34, the uppermajor side surface 54 (FIGS. 5 and 7) of the wedge member slides alongan outer side surface 88 (FIG. 8) of the outer layer 76 of hard corticalbone. The lower major side surface 56 of the wedge member 44 slidesalong an outer side surface 90 of the outer layer 78 of hard corticalbone.

[0069] The outer side surfaces 88 and 90 of the bones 30 and 32 are intheir naturally occurring conditions. Thus, the outer side surfaces 88and 90 of the bones 30 and 32 are not cut away to prepare for insertionof the wedge member 44 into the joint 34. However, it should beunderstood that under certain circumstances that it may be necessary toabrade or otherwise cut the outer side surfaces 88 and 90 of the outerlayers 76 and 78 of hard cortical bone to prepare the joint 34 forinsertion of the wedge member 44.

[0070] As the thin leading end portion 52 (FIG. 8) of the wedge member44 moves into the joint 34, the upper and lower major side surfaces 54and 56 apply force against the outer side surfaces 88 and 90 on thebones 30 and 32. As this occurs, the joint 34 is expanded. As the joint34 is expanded, the bone 32 is pivoted, relative to the bone 30, fromthe initial orientation, shown in FIG. 1, to the improved orientationshown in FIG. 2. As this occurs, the longitudinal central axis 40 of thebone 32 moves relative to the longitudinal central axis 38 of the bone30. Therefore, the angular relationship between the bones 30 and 32 ischanged by expansion of a portion of the joint 34 by insertion of thewedge member 44 into the joint.

[0071] When the wedge member 44 has been pressed the desired distanceinto the joint 34, by the application of force against the thick endportion 50 of the wedge member 44, the outer side surface 60 on thewedge member moves slightly inward of the outer side surfaces on thebones 30 and 32 (FIG. 8). The outer side surface 60 on the wedge member44 has a configuration which corresponds to the configurations of theouter side surfaces on the bones 30 and 32 adjacent to the joint 34.Therefore, the wedge member 44 does not project outward from the joint.This minimizes any tendency of the wedge member to subsequently abradebody tissue adjacent to the joint 34.

[0072] Once the wedge member 44 has been moved into the desiredorientation relative to the bones 30 and 32, as illustratedschematically in FIG. 8, the wedge member 44 is fixedly connected withthe bones 30 and 32 by the screws 70 and 72 to immobilize the joint. Thearea surrounding and directly adjacent to the wedge member 44 is packedwith bone growth promoting material and/or bone chips. The bone growthpromoting materials may include bone morphogenic proteins and/or otherosteoinductive materials. This promotes fusion of the bones 30 and 32for remedial immobilization of the joint 34.

[0073] Since the wedge member 44 is rigid, it can immediately transmitloads between the bones 30 and 32. Therefore, after the incision whichexposed the joint 34 has been closed, the patient can begin to load thejoint 34. The wedge member 44 is effective to maintain the joint 34 inan expanded condition during loading of the joint. Therefore, the bones30 and 32 remain in the improved spatial relationship illustrated inFIG. 2 during loading of the joint 34.

[0074] Wedge Member—Second Embodiment

[0075] In the embodiment of the invention illustrated in FIGS. 1-8, asolid wedge member has been utilized to expand the joint 34. In theembodiment of the invention illustrated in FIG. 9, a porous wedge memberis utilized to expand a joint. Since the embodiment of the inventionillustrated in FIG. 9 is generally similar to the embodiment of theinvention illustrated in FIGS. 1-8, similar numerals will be utilized todesignate similar components, the suffix letter “a” being associatedwith the numerals of FIG. 9 in order to avoid confusion.

[0076] A wedge member 44 a is positioned in a joint 34 a between bones30 a and 32 a. The wedge member 44 a engages outer side surfaces 88 aand 90 a on layers 76 a and 78 a of hard cortical bone. The outer sidesurfaces 88 a and 90 a are in their naturally occurring conditions.

[0077] As the wedge member 44 a is moved into the joint 34 a, flat upperand lower major side surfaces 54 a and 56 a on the wedge member 44 aslide along the outer side surfaces 88 a and 90 a on the bones 30 a and32 a. The upper and lower major side surfaces 54 a and 56 a of the wedge44 a apply force against the outer side surfaces 88 a and 90 a of thebones 30 a and 32 a to expand the joint 34 a as the wedge member ismoved into the joint. The wedge member 44 a is moved into the joint 34 aunder the influence of force applied against an outer side surface 60 aon a trailing thick end portion 50 a of the wedge member 44 a.

[0078] Once the joint 34 a has been expanded to change the spatialrelationship between the bones 30 a and 32 a, suitable fasteners(screws) 70 a and 72 a are inserted through passages in the wedge member44 a. The screws 70 a and 72 a engage the hard cortical outer layers 76a and 78 a of bone to fixedly secure the wedge member 44 a with thebones 30 a and 32 a.

[0079] A single wedge member 44 a is used to expand the joint 34 a.However, a plurality of narrow wedge members 44 a may be inserted intothe joint at spaced apart locations about the periphery of the joint ifdesired.

[0080] In accordance with a feature of this embodiment of the invention,the wedge member 44 a is porous so that bone can grow through the wedgemember. It is contemplated that the wedge member could be provided witha porous construction by having passages extend through the wedge memberbetween the upper and lower major side surfaces 54 a and 56 a of thewedge member. The open ends of the passages would enable bone to growthrough the wedge member 44 a.

[0081] In the embodiment of the wedge member 44 a illustrated in FIG. 9,the wedge member is formed of a rigid open cell material. The open cellmaterial provides cavities in which bone can grow through the wedgemember 44 a. Thus, the wedge member 44 a (FIG. 9) has a cellularconstruction similar to coral.

[0082] It is contemplated that the wedge member 44 a may be coated witha material which promotes the growth of bone. The cells in the wedgemember 44 a may be at least partially filled with bone growth promotingmaterial. The bone growth promoting materials may be bone morphogenicproteins and other osteoinductive materials. In addition to bone growthpromoting material associated with the wedge member 44 a, the spacearound and adjacent to the wedge member 44 a in the joint 34 a may bepacked with bone growth promoting material and/or bone chips.

[0083] The wedge member 44 a is rigid and can be subject to normalloading immediately after being positioned in the joint 34 a. Thisenables the patient to subject the bones 30 a and 32 a to normal loadingwithout waiting for fusion to occur through and around the wedge member44 a. Of course, with the passage of time, the growth of bone throughthe wedge member 44 a and around the wedge member will strengthen theimmobilization of the joint 34 a.

[0084] In the embodiment of the invention illustrated in FIG. 9, thepassages through the wedge member 44 a are formed by the open cellstructure of the wedge member This results in the passages through thewedge member 44 a having an irregular configuration. If desired, linearpassages could be formed in the wedge member 44 a. The linear passagesmay be drilled, cast, or formed in other ways in the wedge member 44 a.

[0085] Hollow Wedge Member

[0086] In the embodiment of the invention illustrated in FIGS. 1-8, thewedge member 44 is formed by a solid piece of material. In theembodiment of the invention illustrated in FIG. 9, the wedge member 44 ais formed by a continuous piece of porous material. In the embodiment ofthe invention illustrated in FIG. 10, the wedge member is formed by ahollow piece of porous material. Since the embodiment of the inventionillustrated in FIG. 10 is generally similar to the embodiments of theinvention illustrated in FIGS. 1-9, similar numerals will be utilized todesignate similar components, the suffix letter “b” being associatedwith the numerals of FIG. 10 to avoid confusion.

[0087] In the embodiment of the invention illustrated in FIG. 10, awedge member 44 b is inserted into a joint 34 b between bones 30 b and32 b to expand the joint. Expansion of the joint 34 b by the wedgemember 44 b changes the spatial relationship between the bones 30 b and32 b. The wedge member 44 b is held against movement relative to thebones 30 b and 32 b by fasteners (screws) 70 b and 72 b. The fasteners70 b and 72 b extend through passages in the wedge member 44 b intolayers 76 b and 78 b of hard cortical bone on bones 30 b, 32 b. Thelayers 76 b and 78 b are in their naturally occurring condition.

[0088] When the wedge member 44 b is to be moved into the joint, a thinend portion 52 b of the wedge member 44 b is pressed into the joint 34 bby applying force against an outer side surface 60 b at a thick endportion 50 b of the wedge member 44 b. The force applied against thetrailing thick end portion 50 b of the wedge member 44 b causes flatupper and lower major side surfaces 54 b and 56 b to slide along outerside surfaces 88 b and 90 b. As the upper and lower major side surfaces54 b and 56 b on the wedge member 44 b slide along the outer sidesurfaces 88 b and 90 b of the bones 30 b and 32 b, the wedge memberapplies force against the bones to expand the joint 34 b in the mannerpreviously explained.

[0089] In accordance with a feature of this embodiment of the invention,the wedge member 44 b (FIG. 10) is hollow. Therefore, a compartment orcavity 100 is formed in the wedge member 44 b. The compartment 100 hasupper and lower inner side surfaces 102 and 104 which are smaller thanthe upper and lower major side surfaces 54 b and 56 b of the wedgemember 44 b. However, the inner side surfaces 102 and 104 of thecompartment 100 have the same general configuration as the upper andlower major side surfaces 54 b and 56 b of the wedge member 44 b.

[0090] The compartment 100 is filled with bone growth inducing material110. The bone growth inducing material 110 is positioned in thecompartment 100 through a suitable opening (not shown) formed in eitherthe upper major side surface 54 b or the lower major side surface 56 bof the wedge member 44 b. Once the compartment 100 has been filled withbone growth inducing material 110, the opening to the compartment isclosed. However, the wedge member 44 b is formed of a porous materialwhich enables bone to grow through the wedge member.

[0091] The growth of bone through the wedge member 44 b is promoted bythe bone growth inducing material 110 in the compartment 100. The bonegrowth inducing material 110 in the compartment 100 may be any of manyknown bone morphogenic proteins and osteoinductive materials. Forexample, apatite compositions with collagen may be utilized.Demineralized bone powder may also be utilized. Regardless of which ofthe known bone growth inducing materials are selected, the presence ofthe bone growth promoting material 110 in the compartment 100 willpromote a growth of bone through openings in the porous wedge member 44b.

[0092] The wedge member 44 b may, itself, be formed of a suitable rigidmaterial, such as tantalum, stainless steel, or ceramic materials. Inaddition to the bone growth inducing material 110, the surfaces of thewedge member 44 b and openings in the porous material of the wedgemember may be coated with suitable bone growth promoting materials.

[0093] The wedge member 44 b is porous so that bone can grow through thewedge member. In the embodiment of the invention illustrated in FIG. 10,the wedge member is formed of an open cell material having aconstruction similar to coral. The open cell material provides irregularpassages which extend through the wedge member 44 b and enable the boneto grow through the wedge member. However, it should be understood thatthe wedge member 44 b could be formed of a solid material with passagesdrilled or cast in the wedge member. Regardless of which of thematerials the wedge member is formed, it is believed that it will beadvantageous to have the material be sufficiently rigid to enable thejoint 44 b to be load bearing immediately after an operation installingthe wedge member in the joint.

[0094] Single Connection for Wedge Member

[0095] In the embodiments of the invention illustrated in FIGS. 8-10,the wedge members 44, 44 a, and 44 b are connected with bones onopposite sides of a joint by suitable fasteners (screws). In theembodiment of the invention illustrated in FIG. 11, the wedge member isconnected with only one of the bones. Since the embodiment of theinvention illustrated in FIG. 11 is generally similar to the embodimentsof the invention illustrated in FIGS. 1-10, similar numerals will beutilized to designate similar components, the suffix letter “c” beingassociated with the numerals of FIG. 11 to avoid confusion.

[0096] A wedge member 44 c is inserted into a joint 34 c between upperand lower bones 30 c and 32 c. The wedge member 44 c has the samegeneral configuration and construction as the wedge member 44 of FIGS.5-8. However, the wedge member 44 c is connected with only one of thebones 30 c and 32 c. Thus, rather than utilizing a pair of fasteners tosecure the wedge member 44 c to the upper and lower bones 30 c and 32 c,only a single fastener 70 c is utilized to connect the wedge member 44 cwith the upper bone 30 c. Therefore, installation of the wedge member 44c in the joint 34 c does not result in immobilization of the joint.

[0097] Since the wedge member 44 c is connected with the bone 30 c bythe fastener 70 c, the bone 32 c may be moved away from the wedge memberduring flexing of the joint 34 c. This may result in the upper majorside surface 54 c on the wedge member 54 c remaining in engagement withthe outer side surface 88 c on the bone 30 c while the outer sidesurface 90 c on the bone 32 c moves away from the lower major sidesurface 56 c on the wedge member 44 c. Of course, a single fastener 70 cmay be utilized to hold the wedge member in the joint 34 c where theouter side surfaces 88 c and 90 c on the upper and lower bones 30 c and32 c remain in engagement with the upper and lower major side surfaces54 c and 56 c of the wedge member 44 c.

[0098] In the embodiment of the wedge member 44 c illustrated in FIG.11, the wedge member is formed of a solid material through which bonedoes not grow. However, it is contemplated that a single fastener,corresponding to the fastener 70 c of FIG. 11, may be used to connect aporous wedge member with a bone. Of course, bone may grow through theporous wedge member. The porous wedge member may have the sameconstruction as shown in FIGS. 9 and 10, with the exception of beingheld in place by only a single fastener 70 c.

[0099] Rotatable Wedge Member

[0100] In the embodiment of the invention illustrated in FIGS. 1-11, thewedge member 44 is moved into the joint 34 between the upper and lowerbones 30 and 32 along a linear path. The wedge member 44 is moved intothe joint 34 with the thin end portion 52 of the wedge member leadingand the thick end portion 50 of the wedge member trailing. The taperedconfiguration of the wedge member results in the application of forceagainst the upper and lower bones 30 and 32 to expand the joint 34 inthe manner previously explained.

[0101] In the embodiment of the invention illustrated in FIGS. 12-16,the wedge member is moved into the joint between the upper and lowerbones and then rotated. During initial movement of the wedge member intothe joint between the bones, there may be some expansion of the joint.During rotation of the wedge member in the joint, there is furtherexpansion of the joint. Since the embodiment of the inventionillustrated in FIGS. 12-15 is generally similar to the embodiments ofthe invention illustrated in FIGS. 1-11, similar numerals will beutilized to designate similar components, the suffix letter “d” beingassociated with the numerals of FIGS. 12-15 to avoid confusion.

[0102] Upper and lower bones 30 d and 32 d are interconnected at a joint34 d (FIG. 12). Prior to insertion of a wedge member 44 d, the upper andlower bones 30 d and 32 d are in the same spatial orientation relativeto each other as is illustrated in FIG. 1. Upon insertion of the wedgemember 44 d into the joint 34 d, in the manner illustrated in FIG. 12,there may be a slight expansion of the joint 34 d and a slight change inthe orientation of the upper bone 30 d relative to the lower bone 32 d.There is a relatively small change in the spatial relationship betweenthe upper bone 30 d and the lower bone 32 d because the wedge member 44d is inserted into the joint 34 d in an orientation in which the wedgemember 44 d is relatively thin as viewed in FIG. 12, that is, in adirection transverse to the joint 34 d.

[0103] After the wedge member 44 d has been inserted into the joint 34 din the manner indicated schematically in FIG. 12, the wedge member 44 dis rotated, through less than one revolution, about an axis 120 in themanner indicated schematically by an arrow 122 in FIG. 13. As the wedgemember 44 d is rotated through approximately ninety degrees about theaxis 120, the wedge member applies force against the upper and lowerbones 30 d and 32 d to expand the joint 34 d. As the joint 34 d isexpanded by rotation of the wedge member 44 d, the spatial relationshipbetween the upper and lower bones 30 d and 32 d changes from the spatialrelationship illustrated schematically in FIG. 12 to the spatialrelationship illustrated schematically in FIG. 13. Thus, by the combinedeffect of insertion of the wedge member 44 d into the joint 34 d androtation of the wedge member in the joint, the spatial relationship ofthe upper and lower bones 30 d and 32 d was changed from the spatialrelationship illustrated in FIG. 1 for the bones 30 and 32 to thespatial relationship illustrated in FIG. 13 for the upper and lowerbones 30 d and 32 d.

[0104] The bones 30 d and 32 d illustrated schematically in FIGS. 12 and13 should be considered as being representative of bones at manydifferent locations in a patient's body. Thus, the bones 30 d and 32 dmay be any of the many bones in a patient's wrist, ankle, hand, foot,back, or other portion of a patient's body. The bones 30 d and 32 d maybe vertebrae in a patient's back. It should be understood that the wedgemember 44 d may be used with any one of the many different types ofjoints in a patient's body.

[0105] The wedge member 44 d has a generally oval, cross-sectionalconfiguration (FIGS. 14 and 15), as viewed in a plane perpendicular to alongitudinal central axis of the wedge member. Thus, the wedge member 44d has an outer side surface 126 (FIG. 14) with a pair of arcuate noseportions 128 and 130. The arcuate nose portions 128 and 130 of the outerside surface 126 are interconnected by a pair of arcuate side portions134 and 136.

[0106] The arcuate outer side surface 126 tapers from a thick endportion 50 d (FIG. 16) to a thin end portion 52 d. In the illustratedembodiment of the wedge member 44 d, the thin end portion 52 d is bluntor truncated. Thus, the thin end portion 52 d of the wedge member 44 ddoes not come to a sharp point as does the thin end portions of thewedge members 44, 44 a, 44 b and 44 c.

[0107] It should be understood that the wedge members 44 a, 44 b and 44c (FIGS. 5-11) could be constructed with a blunt thin end portioncorresponding to the blunt thin end portion 52 d (FIG. 16) on the wedgemember 44 d if desired. However, it is believed that by having the thinend portion of the wedge members of FIGS. 5-11 taper to a sharp point,insertion of the wedge members into a joint is facilitated. Similarly,if desired, the wedge member 44 d could be provided with a thin endportion 52 d (FIG. 16) which comes to a sharp point in the same manneras the wedge members 44, 44 a, 44 b and 44 c.

[0108] When the wedge member 44 d is inserted into the joint 34 d (FIG.14), the arcuate side portion 134 engages the outer side surface 88 d ofthe upper bone 30 d and the arcuate side portion 136 engages the outerside surface 90 d of the lower bone 32 d. The arcuate side portions 134and 136 are relatively close together so that minimal expansion of thejoint 34 d occurs when the wedge member 44 d is inserted into the joint.As the wedge member 44 d is inserted into the joint 34 d, the arcuateside portions 134 and 136 slide along and are effective to apply forceagainst the outer side surfaces 88 d and 90 d of the upper and lowerbones 30 d and 32 d to effect some expansion of the joint 34 d. Theouter side surfaces 88 d and 90 d of the bones 30 d and 32 d are intheir naturally occurring conditions.

[0109] After the wedge member 44 d has been inserted into the joint 34d, in the manner shown in FIGS. 12 and 14, a suitable tool is insertedinto a hexagonal socket 140 (FIG. 14) in the wedge member 44 d. Torqueis transmitted from the tool to the wedge member 44 d to rotate thewedge member through less than one revolution in the direction indicatedby the arrow 122 in FIGS. 13 and 15. This results in the wedge member 44d being rotated through approximately ninety degrees in a clockwisedirection from the position shown in FIG. 14 to the position shown inFIG. 15. As the wedge member 44 d is rotated, the wedge member appliesforce against the upper and lower bones 30 d and 32 d and expands thejoint 34 d.

[0110] Upon initiation of rotation of the wedge member 44 d from theposition shown in FIG. 14 toward the position shown in FIG. 15, thearcuate side portions 134 and 136 slide along the outer side surfaces 88d and 90 d on the bones. As the rotation of the wedge member 44 dcontinues, the arcuate nose portions 128 and 130 of the wedge member 44d approach the outer side surfaces 88 d and 90 d of the upper and lowerbones 30 d and 32 d. As this is occurring, the joint 34 d is expanded bythe force applied against the upper and lower bones 30 d and 32 d by thewedge member 44 d. When the wedge member 44 d reaches the position shownin FIG. 15, the arcuate nose portions 128 and 130 engage the outer sidesurfaces 88 d and 90 d on the upper and lower bones 30 d and 32 d tohold the joint 34 d in the expanded condition illustrated in FIGS. 15and 16.

[0111] A pair of mounting tabs 144 and 146 (FIG. 16) are integrallyformed with the wedge member 44 d. The mounting tabs 144 and 146 projectoutwardly from the end portion 50 d of the wedge member 44 d. Themounting tabs 144 and 146 are aligned with the arcuate nose portions 128and 130 of the outer side surface 126 on the wedge member 44 d.Therefore, the mounting tabs 144 and 146 are disposed adjacent to thebones 30 d and 32 d in the manner illustrated schematically in FIG. 16.

[0112] A pair of retaining screws 70 d and 72 d extend through themounting tabs 144 and 146 into the outer layers 76 d and 78 d of hardcancellous bone on the upper and lower bones 30 d and 32 d. The mountingscrews or fasteners 70 d and 72 d are effective to hold the wedge member44 d against rotation relative to the upper and lower bones 30 d and 32d. Bone growth promoting material and/or bone chips may be packed in thejoint 34 d around the wedge member 44 d. The wedge member 44 d is rigidand can transmit force between the bones 30 d and 32 d as soon as it isrotated to the position shown in FIGS. 15 and 16.

[0113] As is perhaps best seen in FIG. 15, the wedge member 44 d isnarrower than the distance across the joint 34 d. Therefore, a pluralityof wedge members 44 d may be utilized to hold the joint 34 d in theexpanded condition of FIGS. 15 and 16. The plurality of wedge members 44d could be positioned in the joint 34 d with their rotational axes 120(FIG. 16) in a parallel relationship or with their rotational axes 120skewed relative to each other. If a plurality of wedge members 44 d areutilized, they could be of different sizes or have different angles oftaper along the axis 120.

[0114] It should be understood that the wedge members 44, 44 a, 44 b and44 c of FIGS. 5-11 could also be relatively narrow. A plurality of wedgemembers of FIGS. 5-11 could be positioned in a joint with theirlongitudinal axes either parallel or skewed relative to each other.

[0115] Porous Rotatable Wedge Member

[0116] In the embodiment of the invention illustrated in FIGS. 12-16,the wedge member 44 d is formed as a solid body of rigid material, suchas stainless steel. The wedge member in the embodiment of the inventionillustrated in FIG. 17 is formed of a rigid porous material. Since theembodiment of the invention illustrated in FIG. 17 is generally similarto the embodiments of the invention illustrated in FIGS. 1-16, similarnumerals will be utilized to designate similar components, the suffixletter “e” being associated with the numerals of FIG. 17 to avoidconfusion.

[0117] The wedge member 44 e is disposed in a joint 34 e between upperand lower bones 30 e and 32 e. The wedge member 44 e applies forceagainst the outer side surfaces 88 e and 90 e of the upper and lowerbones 30 e and 32 e to expand the joint 34 e and change the orientationof the upper and lower bones relative to each other. In the embodimentof the invention illustrated in FIG. 17, the wedge member 44 e tapersfrom a thick end portion 50 e to a thin end portion 52 e. In theillustrated embodiment of the invention, the thin end portion 52 e ofthe wedge member 44 e has a pointed configuration rather than the bluntconfiguration of the wedge member 44 d of FIG. 16. However, the wedgemember 44 e could have the same configuration as the wedge member 44 dif desired.

[0118] The wedge member 44 e (FIG. 17) has an oval cross sectionalconfiguration, as viewed on a plane extending perpendicular to a centralaxis 120 e of the wedge member 44 e. Thus, the wedge ember 44 e has anouter side surface 126 e with arcuate nose portions 128 e and 130 e. Thearcuate nose portions 128 e and 130 are interconnected by arcuate sideportions corresponding to the arcuate side portions 134 and 136 of thewedge member 44 d (FIGS. 14 and 15). A socket 140 e (FIG. 17) isprovided in the wedge member 44 e to facilitate the application oftorque to the wedge member.

[0119] In accordance with a feature of the embodiment of the inventionillustrated in FIG. 17, the wedge member 44 e is formed of a rigidporous material having an open cell construction. The porous open cellconstruction of the wedge member 44 e enables bone to grow through thewedge member. The wedge member 44 e may have an open cell constructionsimilar to the construction of coral.

[0120] The wedge member 44 e may be coated with bone growth promotingmaterials to promote the growth of bone through the wedge member. Theopen cells in the porous wedge member 44 e could be at least partiallyfilled with the bone growth promoting material. In addition, bone growthmaterials and/or bone chips may be packed in the joint 34 e around thewedge member 44 e. The bone growth promoting materials may include bonemorphogenic proteins and/or other osteoinductive materials.

[0121] A pair of fasteners 70 e and 72 e are provided to connect thewedge member 44 e with the upper and lower bones 30 e and 32 e. Thus,the fasteners 70 e extends into the outer layer 76 e of hard corticalbone on the upper bone 30 e. Similarly, the fastener 72 e extends intothe outer layer 78 e of hard cortical bone on the lower bone 32 e. Inthe illustrated embodiment of the invention, the fasteners 70 e and 72 eextend through passages in the wedge member 44 e into the upper andlower bones 30 e and 32 e. However, if desired, the wedge member 44 ecould be provided with mounting tabs, similar to the mounting tabs 144and 146 of FIG. 16.

[0122] When the wedge member 44 e is to be used to change the spatialrelationship between the upper and lower bones 30 e and 32 e, the wedgemember is inserted into the joint 34 e with the arcuate nose portions128 e and 130 e of the wedge member spaced from the outer side surfaces88 e and 90 e on the upper and lower bones 30 e and 32 e. At this time,the wedge member 44 e is in the same orientation as is illustrated inFIG. 14 for the wedge member 44 d. Arcuate side portions of the arcuateouter side surface 126 e on the wedge member 44 e engage the outer sidesurfaces 88 e and 90 e on the upper and lower bones 30 e and 32 e in thesame manner as is illustrated for the wedge member 44 d in FIG. 14.

[0123] Although inserting the wedge member 44 e into the joint 32 e mayeffect an initial, relatively small expansion of the joint, the majorityof the expansion of the joint 34 e is obtained by rotating the wedgemember 44 e about its central axis 120 e. To rotate the wedge member 44e about its central axis 120 e, a suitable tool is inserted into thesocket 140 e. Force is transmitted from the tool to the wedge member 44e to rotate the wedge member. As the wedge member is rotated relative tothe upper and lower bones 30 e and 32 e, the wedge member furtherexpands the joint 34 e and effects further change in the spatialrelationship between the upper and lower bones 30 e and 32 e.

[0124] Once the wedge member 44 e has been moved to the positionillustrated in FIG. 17, that is, to a position corresponding to theposition of the wedge member 44 d in FIG. 15, the wedge member isconnected to the upper and lower bones 30 e and 32 e. To connect thewedge member with the upper and lower bones 30 e and 32 e, the screws 70e and 72 e are inserted through passages in the wedge member into thebone. Bone growth promoting material and/or bone chips may be packed inthe joint 34 e around the wedge member 44 e.

[0125] Although a single wedge member 44 e is utilized to expand thejoint 34 e, a plurality of wedge members could be utilized if desired.When a plurality of wedge members 34 e are held to expand the joint 34e, the wedge members may all be of the same size and configuration ormay have different sizes and configurations.

[0126] Rotatable Wedge Member Alternative—Embodiment

[0127] The wedge members 44 d and 44 e are rotated about their centralaxes 120 d and 120 e (FIGS. 16 and 17) to effect expansion of the joints34 d and 34 e. In the embodiment of the invention illustrated in FIGS.18 through 20, the wedge member is rotated about a location where thewedge member engages one of the bones. Since the embodiment of theinvention illustrated in FIGS. 18-20 is generally similar to theembodiments of the invention illustrated in FIGS. 1-17, similar numeralswill be utilized to designate similar components, the suffix letter “f”being associated with the numerals of FIGS. 18-20 to avoid confusion.

[0128] Upper and lower bones 30 f and 32 f are interconnected at a joint34 f. A wedge member 44 f is illustrated inserted into the joint 34 fbetween the upper and lower bones 30 f and 32. The wedge member 44 f ispositioned in the joint 34 f (FIG. 18) with a relatively narrow width ofthe wedge member between outer side surfaces 88 f and 90 f on hardcortical outer layers 76 f and 78 f of the upper and lower bones 30 fand 32 f. Although the outer side surfaces 88 f and 90 f of the upperand lower bones 30 f and 32 f are in their naturally occurringconditions, it is contemplated that a surgeon may want to prepare thesurfaces of the bone for the wedge member 44 f by cutting awayextraneous material to promote seating of the wedge member 44 f on theupper and lower bones 30 f and 32 f.

[0129] The wedge member 44 f has an arcuate nose portion 128 f and apivot end portion 150 f. The nose portion 128 f and pivot end portion150 f are interconnected by side portions 134 f and 136 f. The sideportion 134 f has a continuously curving arcuate configuration. The sideportion 136 f may have a linear configuration.

[0130] The side portion 136 f has a relatively flat area which engagesthe outer side surface 90 f on the lower bone 32 f when the wedge member44 f is oriented as illustrated in FIG. 18 If desired, the side portion136 f could have an arcuate configuration corresponding to the arcuateconfiguration of the side portion 134 f. If the side portion 136 f hadthe same configuration as the side portion 134 f, the wedge member 44 fwould have a symmetrical configuration about an axis extending throughthe relatively sharply defined pivot end portion 150 c.

[0131] The wedge member 44 f has the same size and configurationthroughout its length. Thus, the end portion SOf of the wedge member isthe same size as the end portion 52 f (FIG. 20). However, if desired,the wedge member 44 f could taper from a relatively thick end portion 50f to a relatively thin or small end portion 52 f in the mannerillustrated in FIGS. 16 and 17 for the wedge members 44 d and 44 e. Itshould be understood that any one of the wedge members illustrated inFIGS. 1 through 17 could be formed with the same configuration as thewedge member 44 f if desired. However, it is believed that in mostinstances it will probably be preferred to provide the wedge members ofFIGS. 1-17 with an axially tapered configuration to facilitate insertionof the wedge members into the joint between the upper and lower bones.

[0132] The wedge member 44 f (FIGS. 18, 19 and 20) is formed of a rigidporous open cell material. The rigid porous open cell material of thewedge member 44 f has a construction generally similar to coral.However, the wedge member 44 f could be formed of a nonporous materialif desired.

[0133] It is contemplated that the wedge member 44 f, like the wedgemembers illustrated in FIGS. 1-17, may be formed of human or animalbone, metal, ceramic, or a polymeric material. While it may be preferredto form the wedge member 44 f of a porous material to enable bone togrow through the wedge member, the wedge member 44 f may be formed of asolid material through which bone can not grow.

[0134] The wedge member 44 f may be coated with or packed with bonegrowth promoting materials. The bone growth promoting materials may bebone morphogenic proteins and/or other osteoinductive materials. Bonechips may be included with the bone morphogenic proteins and/or otherosteoinductive materials packed around the wedge member 44 f.

[0135] Of course, the wedge member 44 f may be provided with a taperedconfiguration to facilitate insertion into the joint 34 f. When thewedge member 44 f is to be utilized to change the spatial relationshipbetween the upper and lower bones 30 f and 32 f, the wedge member isinserted into the joint 34 f. The illustrated embodiment of the wedgemember 44 f has the same size and configuration throughout its length.Therefore, the wedge member 44 f does not taper to a thin end portion tofacilitate insertion of the wedge member into the joint 34 f. Therefore,the joint 34 f may be initially expanded with a suitable tool to enablethe wedge member 44 f to be inserted into the joint, in the orientationillustrated in FIG. 18.

[0136] When the wedge member 44 f is inserted into the joint 34 f, therewill be a slight initial expansion of the joint. As was previouslymentioned, the wedge member 44 f may have an axially taperedconfiguration, similar to the configuration of the wedge members 44 dand 44 e (FIGS. 16 and 17), to facilitate insertion of the wedge member44 f into the joint 34 f.

[0137] As the wedge member 44 f is initially inserted into the joint 34f, the side portions 134 f and 136 f on the wedge member 44 f slidealong the outer side surfaces 88 f and 90 f on the upper and lower bones30 f and 32 f. At this time, the arcuate nose portion 128 f of the wedgemember 44 f is spaced from the outer side surface surfaces 88 f and 90 fof the upper and lower bones 30 f and 32 f.

[0138] To further change the spatial relationship between the upper andlower bones 30 f and 32 f, the wedge member 44 f is rotated about anaxis extending through a location where the pivot end portion 150 f ofthe wedge member 44 f engages the outer side surface 90 f of the lowerbone 32 f. To effect rotation of the wedge member 44 f, a suitable toolis inserted into a socket 140 f. Force is transmitted through the toolto the wedge member 44 f urging the wedge member 44 f to rotate in aclockwise direction from the position shown in FIG. 18 to the positionshown in FIG. 19.

[0139] Upon initial application of the force to the wedge member 44 furging the wedge member to rotate in a clockwise direction (as viewed inFIG. 18), the pivot end portion 150 f of the wedge member 44 f ispressed against the outer side surface 90 f of the lower bone 32 f. Atthe same time, the side portion 134 f of the wedge member 44 f begins toslide along the outer side surface 88 f on the upper bone 30 f.

[0140] Continued application of force (torque) to the wedge member 44 fresults in the wedge member pivoting about an axis which extends througha location where the end portion 150 f of the wedge member 44 f engagesthe outer side surface 90 f on the lower bone 32 f. As the wedge member44 f pivots about the end portion 150 f, the arcuate nose portion 128 fmoves into engagement with and slides along the outer side surface 88 fon the upper bone 30 f. As the wedge member 44 f approaches theorientation shown in FIG. 19, the joint 34 f is expanded and the spatialrelationship between the upper and lower bones 30 f and 32 f is changedwith a resulting change in the angular orientation of the upper andlower bones relative to each other.

[0141] When the wedge member 44 f reaches the orientation shown in FIG.19, the joint 34 f has been expanded to the maximum extent possible bythe wedge member. The wedge member 44 f is then connected with the upperand lower bones 30 f and 32 f by suitable fasteners. The fasteners mayextend through mounting tabs, similar to the mounting tabs 144 and 146illustrated in FIG. 16 or the fasteners may extend through the wedgemember in the manner illustrated schematically in FIG. 17. Of course,the wedge member 44 f could be held in the upright (as viewed in FIG.19) orientation in any one of many different manners by a suitablefastener arrangement.

[0142] Although only a single wedge member 44 f has been shown in FIGS.18-20, a plurality of the wedge members 44 f could be used to expand thejoint 34 f and to transmit force between the bones 30 f and 32 f.Whether a single wedge member 44 f or a plurality of wedge members 44 fare used to expand the joint, the joint may be packed with bone growthpromoting material.

[0143] Screw Type Wedge Member

[0144] In the embodiment of the invention illustrated in FIGS. 12-16,the wedge member 44 d has a relatively smooth outer side surface 126. Inthe embodiment of the invention illustrated in FIGS. 21 and 22, thewedge member has a configuration similar to the configuration of a screwand has a irregular outer side surface. Since the embodiment of theinvention illustrated in FIGS. 21 and 22 is generally similar to theembodiments of the invention illustrated in FIGS. 12-20, similarnumerals will be utilized to designate similar components, the suffixletter “g” being associated with the numerals of FIGS. 21 and 22 toavoid confusion.

[0145] An upper bone 30 g is connected with a lower bone 32 g in apatient's body at a joint 34 g. It should be understood that the joint34 g has been illustrated schematically in FIG. 21 and may be any jointin a patient's body. A rigid wedge member 44 g is utilized to change thespatial relationship between the upper and lower bones 30 g and 32 g.The wedge member 44 g is effective to expand at least a portion of thejoint 34 g when the wedge member 44 g is inserted into the joint 34 g.

[0146] The wedge member 44 g has a thick end portion 50 g and a thin endportion 52 g. The wedge member 44 g has an overall conicalconfiguration. An external thread convolution 160 is formed on the wedgemember 44 g. The external thread convolution 160 has a spiralconfiguration and extends from the thick end portion 50 g to the thinend portion 52 g of the wedge member 44 g.

[0147] Although the external thread convolution 160 could have manydifferent configurations, the illustrated thread convolution hasgenerally V-shaped crests and roots. The general configuration of theexternal thread convolution 160 is an American National Form ScrewThread and has a pitch cone with an angle of between five degrees andtwenty degrees. Although one specific external thread convolution hasbeen illustrated and described herein, it should be understood that theexternal thread convolution 160 could have a configuration of any one ofmany different known thread convolutions. It is believed that it may bedesired to use known bone screw thread configurations for theconfiguration of the external thread convolution 160.

[0148] The rigid wedge member 44 g may be formed of metal, ceramic,human or animal bone, or suitable polymeric materials. It is believedthat it will be desirable to form the wedge member 44 g of a materialwhich is sufficiently rigid to withstand the forces transmitted betweenthe upper and lower bones 30 g and 32 g. If desired, the wedge member 44g may be formed of a porous material having openings through which bonemay grow. It is believed that it may be desired to coat the wedge member44 g with a bone growth promoting material.

[0149] When the wedge member 44 g is to be utilized to change thespatial relationship between the upper and lower bones 30 g and 32 g,the thin end portion 52 g of the wedge member 44 g is pressed into thejoint 34 g between the upper and lower bones 30 g and 32 g. The wedgemember 44 g is then rotated about its longitudinal central axis 120 g. Ahexagonal recess 140 g is provided in the wedge member 44 g tofacilitate the transmission of force from a suitable tool to the wedgemember 44 g.

[0150] As the wedge member 44 g is rotated through a plurality ofrevolutions about its longitudinal central axis 120 g, the externalthread convolution 160 g engages the upper and lower bones 30 g and 32g. As the wedge member 44 g is rotated about its longitudinal central120 g, the external thread convolution 160 engages the upper and lowerbones 30 g and 32 g and pulls the wedge member into the joint 34 g. Asthis occurs, the joint 34 g is expanded and the spatial relationshipbetween the upper and lower bones 30 g and 32 g is changed.

[0151] Once the wedge member 44 g has moved into the joint 34 g and thespatial relationship between the upper and lower bones 30 g and 32 g hasbeen changed, the joint 34 g may be packed with bone growth promotingmaterials and/or bone chips. It is contemplated that various known bonemorphogenic proteins may be used with other osteoinductive materials toinduce bone growth in the joint 34 g. Although only a single wedgemember 44 g is illustrated in FIG. 21, a plurality of wedge members maybe used if desired.

[0152] Bone Fitting Wedge Member

[0153] In the embodiments of the invention illustrated in FIGS. 1-11,the wedge members have flat upper and lower major side surfaces 54 and56 (FIG. 6). In the embodiment of the invention illustrated in FIGS. 23and 24, the wedge member has nonlinear side surfaces which have beenshaped to correspond to the configuration of end portions of the bone ata joint between the bones. Since the embodiment of the inventionillustrated in FIGS. 23 and 24 is generally similar to the embodimentsof the invention illustrated in FIGS. 1-11, similar numerals will beutilized to designate similar components, the suffix letter “h” beingassociated with the numerals of FIG. 9 to avoid confusion.

[0154] Upper and lower bones 30 h and 32 h are interconnected at a joint34 h. The joint 34 h is a schematic representation of any one of manyjoints in a patient's body. The joint 34 h may be in a patient's wrist,ankle, hand, foot, back, or other portion of the patient's body.

[0155] When the spatial relationship between the upper and lower bones30 h and 32 h is to be changed, a wedge member 44 h is moved into thejoint 34 h. The wedge member 44 h is moved into the joint with a thickend portion 50 h of the wedge member trailing and a thin end portion 52h of the wedge member leading. As the wedge member 44 h is pressed intothe joint 34 h, upper and lower major side surfaces 54 h and 56 h arepressed against outer side surfaces 88 h and 90 h on the upper and lowerbones 30 h and 32 h. This results in expansion of the joint 34 h in themanner previously described in conjunction with the embodiments of theinvention illustrated in FIGS. 1-11.

[0156] In accordance with a feature of this embodiment of the invention,the upper and lower major side surfaces 54 h and 56 h on the wedgemember 44 h are configured to match the configuration of the outer sidesurfaces 88 h and 90 h on the upper and lower bones 30 h and 32 h, inthe manner illustrated schematically in FIG. 24. By having the upper andlower major side surfaces 54 h and 56 h configured to match theconfiguration of the outer side surfaces 88 h and 90 h on the upper andlower bones 30 h and 32 h, the wedge member 44 h is firmly seatedagainst the bone and held against sidewise (as viewed in FIG. 24)movement relative to the bones. The arcuate configuration of the upperand lower major side surfaces 54 h and 56 h on the wedge member 44 hextends from the thick end 50 h of the wedge member 44 h to the thin end52 h of the wedge member.

[0157] In the embodiment of the invention illustrated in FIG. 24, thewedge member 44 h is formed of a rigid porous material having an opencell construction. A compartment or cavity 100 h in the wedge member 44h holds bone growth inducing materials 110 h. The bone growth inducingmaterials 110 h may include bone morphogenic proteins and otherosteoinductive materials. The joint 34 h may be packed with bone growthpromoting materials and/or bone chips.

[0158] The wedge member 44 h is fixedly connected to the upper and lowerbones 30 h and 32 h by suitable fasteners (not shown). The wedge member44 h may be connected with the upper and lower bones 30 h and 32 h byscrews corresponding to the screws 70 and 72 of FIG. 8. Alternatively,the wedge member 44 h may be connected with the upper and lower bone 30h and 32 h by screws which extends through mounting tabs, correspondingto the mounting tabs 144 and 146 of FIG. 16. If desired, the wedgemember 44 h may be connected with only the upper bone 30 h or only thelower bone 32 h.

[0159] It is believed that by having the side surfaces 54 h and 56 hconfigured to correspond to the configuration of the surfaces 88 h and090 h on the bones 30 h and 32 h, the joint 34 h will be particularlystable when the joint has been immobilized by connecting the wedgemember 44 h to the bones. Although only a single wedge member 34 h hasbeen illustrated in FIGS. 22 and 24, a plurality of wedge members couldbe used to expand the joint. It is believed that the wedge member 44 hmay be particularly advantageous when vertebrae in a patient's back areto be interconnected.

[0160] Conclusion

[0161] In view of the foregoing description it is apparent that a newand improved method and apparatus is provided to change a spatialrelationship between bones 30 and 32 which are interconnected at a joint34 in a patient's body. When this is to be done, an opening is formed ina portion of the patient's body to expose the joint 34 interconnectingthe bones 30 and 32. One of the bones 30 and 32 is moved relative to theother by expanding at least a portion of the joint 34 with a wedgemember 44. The wedge member 44 is moved into the joint and applies forceagainst the bones 30 and 32. The opening is closed with the wedge member44 still disposed in the joint between the bones. Force is thentransmitted between the bones 30 and 32 through the wedge member 44 tomaintain the joint 34 in an expanded condition.

[0162] If the joint 34 is to be flexed after being expanded by the wedgemember 44, the wedge member may be connected with only one of the bones30 and 32. Alternatively, if the joint 34 is to be immobilized (fused)after inserting the wedge member 44, the wedge member may be fixedlyconnected with the bones 30 and 32 interconnected at the joint. Thewedge member 44 may be porous and may be coated with and/or contain bonegrowth promoting material.

[0163] One embodiment of the wedge member 44 has major side surfaces 54and 56 extending between thick and thin end portions 50 and 52 of thewedge member. The wedge member 44 is moved into the joint 34 with thethin edge portion 52 leading. As the wedge member 44 is moved into thejoint 34, the thick trailing end portion 50 of the wedge member expandsthe joint.

[0164] In another embodiment of the invention, the wedge member 44 d, 44e, 44 f, or 44 g may be rotated relative to the joint. In one embodimentof the invention, the wedge member 44 g has a circular cross sectionalconfiguration and has an external thread convolution 160 which extendsfrom a thin leading end 52 g of the wedge member to a thick trailing end50 g of the wedge member. The wedge member 44 g is pressed into thejoint 34 g and rotated to cause the wedge member to expand the joint.

[0165] In another embodiment of the invention, the wedge member 44 d, 44e or 44 f has surface areas 134 and 136 which are relatively closetogether and other surface areas 128 and 130 which are relatively farapart. The wedge member 44 d, 44 e, or 44 f is moved into the joint 34with the surface areas 134 and 136 which are close together engaging theadjacent bones 30 and 32. The wedge member 44 d, 44 e or 44 f is thenrotated to apply force against the adjacent bones to expand the joint.The wedge member 44 d or 44 e may be rotated about its central axis 120to apply forced against the bones 30 and 32 and expand the joint.Alternatively, the wedge member 44 f may be rotated about a locationwhere the wedge member engages one of the bones.

[0166] Regardless of which embodiment of the wedge members 44, 44 a, 44b, 44 c, 44 d, 44 e, 44 f, 44 g or 44 h is selected, the wedge membermay be used with any one of the many different bones and joints in apatient's body. The wedge member may be utilized at joints in apatient's wrist, ankle, hand, foot, back, or other portions of thepatient's body. The use of the wedge member may be particularlyadvantageous when a joint between vertebrae in a patient's back is to beimmobilized. One or more wedge members may be used to expand a joint totransmit force between bones.

Having described the invention, the following is claimed:
 1. A method ofchanging a spatial relationship between first and second bones which areinterconnected at a joint in a patient's body, said method comprisingthe steps of forming an opening in a portion of the patient's body toexpose the joint interconnecting the first and second bones, moving thesecond bone relative to the first bone, said step of moving the secondbone relative to the first bone includes expanding at least a portion ofthe joint interconnecting the first and second bones by applying forceagainst the first and second bones with a wedge member, closing theopening in the patient's body with at least a portion of the wedgemember disposed between the first and second bones at the jointinterconnecting the first and second bones, and, thereafter,transmitting force between the first and second bones through the wedgemember to maintain the joint in the expanded condition.
 2. A method asset forth in claim 1 wherein said step of applying force against thefirst and second bones with the wedge member includes sliding a firstsurface on the wedge member along an outer side surface on the firstbone and sliding a second surface on the wedge member along an outerside surface on the second bone.
 3. A method as set forth in claim 1wherein said step of applying force against the first and second boneswith a wedge member includes rotating the wedge member about an axiswhich extends through the joint interconnecting the first and secondbones.
 4. A method as set forth in claim 1 wherein said step of movingthe second bone relative to the first bone includes pivoting the secondbone relative to the first bone about an axis which extends through thejoint interconnecting the first and second bones.
 5. A method as setforth in claim 1 wherein said wedge member tapers from a thick endportion to a thin end portion, said thin end portion of said wedgemember being disposed between ends of said first and second bones at thejoint interconnecting the first and second bones and said thick endportion of said wedge member being disposed adjacent to a portion of thejoint which was expanded during performance of said step of applyingforce against the first and second bones with a wedge member.
 6. Amethod as set forth in claim 1 wherein the first and second bones areinterconnected for pivotal movement about a first axis at the jointinterconnecting the first and second bones, said step of applying forceagainst the first and second bones with a wedge member includes movingthe wedge member into the joint in a direction extending along the firstaxis.
 7. A method as set forth in claim 1 wherein the first and secondbones are interconnected for pivotal movement about a first axis at thejoint interconnecting the first and second bones, said step of applyingforce against the first and second bones with a wedge member includesmoving the wedge member into the joint in a direction extendingtransverse to the first axis.
 8. A method as set forth in claim 1wherein the first and second bones are interconnected for pivotalmovement about a first axis at the joint interconnecting the first andsecond bones, said step of applying force against the first and secondbones with a wedge member includes applying force against the first andsecond bones with a wedge member having an extent along the first axiswhich is less than the extent of the joint along the first axis.
 9. Amethod as set forth in claim 1 wherein the wedge member has first andsecond arcuate surface areas, said step of applying force against thefirst and second bones with the wedge member includes rotating the wedgemember about an axis which is disposed between the first and secondarcuate surface areas and transmitting force to the first and secondbones from the first and second arcuate surface areas during rotation ofthe wedge member about the axis disposed between the first and secondarcuate surface areas.
 10. A method as set forth in claim 9 wherein saidstep of rotating the wedge member includes rotating the wedge memberthrough a distance which is less than one complete revolution about theaxis disposed between the first and second arcuate surface areas.
 11. Amethod as set forth in claim 10 wherein the wedge member tapers from athick portion to a thin portion in a direction along the axis aboutwhich the wedge member is rotated, said step of expanding the jointinterconnecting the first and second bones includes expanding a portionof the joint adjacent to the thick portion of the wedge member to agreater extent than a portion of the joint adjacent to the thin portionof the wedge member.
 12. A method as set forth in claim 1 wherein thewedge member has first and second surface areas each of which is spaceda first distance from a central axis of said wedge member and third andfourth surface areas each of which is spaced a second distance from acentral axis of said wedge member, said second distance being greaterthan said first distance, said step of moving the second bone relativeto the first bone includes positioning the wedge member between thefirst and second bones with the first surface area on the wedge memberin engagement with a first surface area on the first bone and the secondsurface area on the wedge member in engagement with a first surface areaon the second bone, said step of expanding the joint includes rotatingthe wedge member about its central axis and moving the third surfacearea on the wedge member into engagement with the first surface area onthe first bone and moving the fourth surface area on the wedge memberinto engagement with the first surface area on the second bone.
 13. Amethod as set forth in claim 1 wherein said wedge member has first andsecond surface areas which are spaced a first distance apart, said wedgemember has third and fourth surface areas which are spaced a seconddistance apart, said second distance being greater than said firstdistance, said step of moving the second bone relative to the first boneincludes positioning the wedge member between the first and second bonesand rotating the wedge member from a first position in which the firstand second surface areas are adjacent to surfaces on the first andsecond bones to a second position in which the third and fourth surfaceareas are adjacent to the surfaces on the first and second bones.
 14. Amethod as set forth in claim 1 wherein said wedge member has a cornerportion where first and second surface areas on said wedge member areinterconnected and an arcuate side surface which is spaced from saidcorner portion, said step of moving the second bone relative to thefirst bone includes pivoting the wedge member about an axis which isdisposed adjacent to the corner portion of said wedge member.
 15. Amethod as set forth in claim 14 wherein said step of pivoting the wedgemember includes engaging the first bone with the corner portion of thewedge member and sliding the arcuate side surface of the wedge memberalong an outer side surface on the second bone.
 16. A method as setforth in claim 1 wherein the wedge member has surfaces which define aplurality of openings extending through said wedge member, said methodfurther includes growing body tissue through the openings in the wedgemember.
 17. A method as set forth in claim 1 wherein said wedge memberis hollow and contains body tissue growth promoting material, saidmethod further includes growing body tissue through openings in saidwedge member.
 18. A method of changing a spatial relationship betweenfirst and second bones which are interconnected at a joint in apatient's body, said method comprising the steps of moving a wedgemember into the joint between the first and second bones with a thin endportion of the wedge member leading and a thick end portion of the wedgemember trailing to move the second bone from a first orientationrelative to the first bone to a second orientation relative to the firstbone, fixedly connecting the wedge member to at least one of the firstand second bones, and transmitting force between the first and secondbones through the wedge member while the second bone is in the secondorientation relative to the first bone.
 19. A method as set forth inclaim 18 wherein a first surface area on said first bone is adjacent toa first surface area on said second bone when the first and second bonesare in the first orientation prior to performance of said step of movingthe wedge member into the joint, said step of moving the wedge memberinto the joint includes sliding a first surface area on the wedge memberalong the first surface area on the first bone and sliding a secondsurface area on the wedge member along the first surface area on thesecond bone to move the first surface area on the second bone away fromthe first surface area on the first bone under the influence of forceapplied against the first surface area on the second bone by the wedgemember.
 20. A method as set forth in claim 19 further including thesteps of maintaining the wedge member stationary relative to said one ofsaid first and second bones during movement of another of said first andsecond bones relative to said one of said first and second bones afterperformance of said step of fixedly connecting the wedge member to saidone of said first and second bones.
 21. A method as set forth in claim18 wherein said step of moving a wedge member into a joint between thefirst and second bones includes rotating the wedge member about an axiswhich extends through the thick and thin end portions of the wedgemember.
 22. A method as set forth in claim 18 wherein said step ofmoving the wedge member into the joint between the first and secondbones includes moving the wedge member along a path which extendsbetween an end portion of the first bone and an end portion of thesecond bone.
 23. A method as set forth in claim 22 wherein said step ofmoving the wedge member along a path which extends between the endportions of the first and second bones includes increasing a distancebetween a surface area on the end portion of the first bone and asurface area on the second bone under the influence of force transmittedfrom the wedge member to the end portions of the first and second bones.24. A method as set forth in claim 23 wherein said step of fixedlyconnecting the wedge member to at least one of the first and secondbones includes fixedly connecting the wedge member to only the endportion of the first bone to enable the end portion of the second boneto move relative to the wedge member under the influence of forceapplied against the second bone by the patient.
 25. A method of changinga spatial relationship between first and second bones which areinterconnected at a joint in a patient's body, said method comprisingthe steps of moving a wedge member into a joint between end portions ofthe first and second bones, and, thereafter, rotating the wedge memberfrom a first orientation in which first and second surface areas on thewedge member are in engagement with the end portions of the first andsecond bones to a second orientation in which third and fourth surfaceareas on the wedge member are in engagement with the end portions of thefirst and second bones, the third and fourth surface areas on the wedgemember being spaced further apart than the first and second surfaceareas on the wedge member.
 26. A method as set forth in claim 25 whereinsaid step of rotating the wedge member from a first orientation to asecond orientation includes rotating the wedge member about an axiswhich extends through the wedge member at a location between the firstand second surface areas.
 27. A method as set forth in claim 25 whereinsaid step of rotating the wedge member includes rotating the wedgemember through a distance which is less than one complete revolution ofthe wedge member.
 28. A method as set forth in claim 25 wherein saidstep of rotating the wedge member from the first orientation to thesecond orientation includes rotating the wedge member about a locationwhere the wedge member engages the first bone.
 29. A method as set forthin claim 25 wherein said step of rotating the wedge member from thefirst orientation to the second orientation includes sliding the wedgemember along a surface area on the end portion of the second bone.
 30. Amethod as set forth in claim 29 wherein said step of rotating the wedgemember from the first orientation to the second orientation includessliding the wedge member along a surface area on the end portion of thefirst bone.
 31. A method as set forth in claim 29 wherein said step ofrotating the wedge member from the first orientation to the secondorientation includes rotating the wedge member about a location wherethe wedge member engages the first bone.
 32. A method as set forth inclaim 25 further including the step of fixedly connecting the wedgemember to at least one of the first and second bones to hold the wedgemember against rotation from the second orientation back toward thefirst orientation.
 33. A method of changing the spatial relationshipbetween first and second bones which are interconnected at a joint in apatient's body, said method comprising the steps of moving the secondbone from a first orientation to a second orientation relative to thefirst bone, said step of moving the second bone from a first orientationto a second orientation includes moving a wedge member into the jointbetween the first and second bones and transmitting force from the wedgemember to the second bone to move the second bone relative to the firstbone, thereafter, connecting the wedge member to the first bone, andmoving the second bone relative to the wedge member and the first boneunder the influence of force transmitted from muscular body tissue inthe body of the patient to the second bone to thereby change theorientation of the second bone relative to the first bone from thesecond orientation to a third orientation.
 34. A method as set forth inclaim 33 wherein said steps of moving a wedge member into the jointbetween the first and second bones and transmitting force from the wedgemember to the second bone to move the second bone relative to the firstbone includes expanding at least a portion of the joint by applyingforce against the first and second bones with the wedge member.
 35. Amethod as set forth in claim 33 further including the step oftransmitting force between the first and second bones through the wedgemember while the second bone is in the second orientation.
 36. A methodas set forth in claim 33 wherein said step of moving the second bonerelative to the wedge member and the first bone includes moving asurface area on the second bone out of engagement with the wedge member.37. A method as set forth in claim 33 wherein said step of moving awedge member into the joint between the first and second bones includesmoving the wedge member into the joint between the first and secondbones with a thin end portion of the wedge member leading and a thickend portion of the wedge member trailing.
 38. A method as set forth inclaim 33 wherein said steps of moving a wedge member into the jointbetween the first and second bones and transmitting force from the wedgemember to the second bone includes rotating the wedge member through aplurality of revolutions about an axis which extends through the wedgemember.
 39. A method as set forth in claim 33 wherein said steps ofmoving a wedge member into the joint between the first and second bonesand transmitting force from the wedge member to the second bone includesrotating the wedge member through less than one complete revolutionabout an axis which extends through the wedge member.
 40. A method ofchanging a spatial relationship between first and second bones which areinterconnected at a joint in a patient's body, said method comprisingthe steps of moving the second bone from a first orientation to a secondorientation relative to the first bone, said step of moving the secondbone from a first orientation to a second orientation includes moving awedge member into the joint between the first and second bones andtransmitting force from the wedge member to the second bone to move thesecond bone relative to the first bone, and, thereafter, immobilizingthe joint with the second bone in the second orientation relative to thefirst bone and with the wedge member in the joint between the first andsecond bones.
 41. A method as set forth in claim 39 wherein said step ofimmobilizing the joint includes packing the joint with bone growthpromoting material.
 42. A method as set forth in claim 39 wherein saidstep of immobilizing the joint includes growing body tissue through aplurality of openings in the wedge member.
 43. A method as set forth inclaim 39 wherein said step of immobilizing the joint includes fixedlyconnecting the wedge member to the first and second bones with thesecond bone in the second orientation relative to the first bone.
 44. Amethod of changing a spatial relationship between first and second boneswhich are interconnected at a joint in a patient's body, said methodcomprising the steps of moving the second bone from a first orientationto a second orientation relative to the first bone, said step of movingthe second bone from a first orientation to a second orientationincludes moving a wedge member into the joint between the first andsecond bones and transmitting force from the wedge member to the secondbone to move the second bone relative to the first bone, and,thereafter, growing bone between the first and second bones through thewedge member while the second bone is in the second orientation relativeto the first bone.
 45. A method as set forth in claim 44 furtherincluding the step of promoting growth of bone through said wedge memberby providing bone growth promoting material in said wedge member.
 46. Amethod as set forth in claim 44 further including the steps of fixedlyconnecting the wedge member to the first bone and fixedly connecting thewedge member to the second bone with the second bone in the secondorientation relative to the first bone, said steps of fixedly connectingthe wedge member to the first and second bones being performed prior toperformance of said step of growing bone through the wedge member.
 47. Amethod as set forth in claim 44 wherein the wedge member tapers from athick end portion to a thin end portion, said step of moving a wedgemember into the joint between the first and second bones is performedwith the thin end portion of the wedge member leading and thick endportion of the wedge member trailing, said step of growing bone throughthe wedge member includes growing bone through surfaces which aredisposed on the wedge member and extend between the thick and thin endportions of the wedge member.
 48. A method as set forth in claim 47wherein said step of moving the wedge member into the joint between thefirst and second bones includes rotating the wedge member about an axiswhich extends between thick and thin end portions of the wedge member.49. A method as set forth in claim 47 further including the step ofpromoting the growth of bone through the wedge member by providing bonegrowth promoting material in the wedge member at a location between thesurfaces which are disposed on the wedge member and extend between thethick and thin end portions of the wedge member.
 50. An apparatus foruse in changing the spatial relationship between first and second boneswhich are interconnected at a joint in a patient's body, said apparatuscomprising a wedge member which is movable into the joint between thefirst and second bones, said wedge member having first and secondsurfaces which transmit force to the first and second bones to expand atleast a portion of the joint between the first and second bones, saidwedge member having a plurality of passages which extend between thefirst and second surfaces for enabling bone to grow through said wedgemember.
 51. A method as set forth in claim 50 further including aconnector element extending from said wedge member to the first bone tofixedly connect said wedge member with the first bone.